Power has been restored to 30 properties in Christchurch after a shorting cable triggered a series of small underground explosions on Thursday.
The blasts were found to be coming from a low voltage power cable in the suburb of Riccarton that was shorting due to a fault.
The Fire Service says it received reports of explosions and flashes of fire coming from a drain on the corner of Riccarton and Straven Road about 1pm.
Lines company Orion says the power was restored about 9pm.